Often you can get a thermocouple that is not working to work again. Simply clean the tubular looking part with some fine sandpaper, steel wool or emory cloth. You may have to get creative and wrap it around a small screwdriver. Additionally make sure the pilot orfice is clear (like Disesasel mentioned) and finally, sometimes you can slightly bend the thermocouple or the flame deflector into the flame more so it gets hotter. There may also be a pilot adjustment screw but if you are not familiar with gas valves I would not suggest messing with that, it is usually located under a cap screw and if the orfice is clean there is no need to increase the flame. Cleaning the pilot orfice usually will result in a better flame. A tiny wire will work if you have no orfice drills, DO NOT ENLARGE THE ORFICE. Cleaning the orfice while holding the pilot button down will allow the gas to flow and push the tiny bits of carbon out as you are cleaning instead of them dropping down into the supply tube.

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Brian
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